As servers become cheaper, more numerous, and more complex, managing them becomes a greater proportion of data-center cost. To monitor the health of a data center, system software is generally configured to generate events when significant state changes or errors occur. These events are written to an event log, where they can be analyzed by humans or manageability software to diagnose problems, determine appropriate repair actions, and the like. With increasing complexity, logs grow in size, and with data center scale-out they grow in number. Thus, human analysis of event logs to accurately diagnose system problems becomes more difficult and time consuming. Additionally, such event logs are generally not well suited for large-scale automated analysis.